The invention discloses a non-transferred-arc plasma gun. The non-transferred-arc plasma gun includes a housing, an anode structural member, a cathode structural member, an arc leading pin and a fluidchannel. The anode structural member is provided with an arc leading hole. The cathode structural member is spaced from the anode structural member. The arc leading pin is arranged in the arc leadinghole in a movable manner. The arc leading pin is in contact with the cathode structural member. The fluid channel cools the anode structural member and the cathode structural member through cooling water. According to the invention, through arranging the arc leading hole in the anode structural member and allowing the arc leading pin to move in the arc leading hole, the anode structural member and the cathode structural member can be connected via the arc leading pin and ignition can be achieved, so that simple structure and convenient operation are achieved. Besides, the fluid channel can cool the anode structural member and the cathode structural member, so that fusion of the arc leading pin in the arc leading hole can be prevented and further the arc leading pin left in the arc leadinghole can be utilized for plugging the arc leading hole and ejection of plasma gas from the arc leading hole can be prevented. Therefore, the performance of the non-transferred-arc plasma gun is improved.